One method of producing 7-acylamido cephalosporins, used medicinally as antibiotics, comprises preparing the analogous 7-amino cephalosporin and then acylating the 7-amino group to produce the desired product. This method suffers from the disadvantage that it is necessary to first isolate and purify the intermediate 7-amino cephalosporin. Accordingly, other methods have been sought which would avoid the need of preparing the 7-amino cephalosporin intermediate.
More recently it has been found that 7.beta.-acylamido cephalosporins having a methoxy substituent in place of the hydrogen substituent at the 7-position are produced by various microorganisms. These cephalosporins contain an aminoadipoyl sidechain at the 7-position which is preferably interchanged with an acyl sidechain which provides a 7.beta.-acylamido-7.alpha.-methoxy cephalosporin of enhanced antibiotic activity.